Use Foldr with Hugging Face Chat UI (MCP)
HF Chat UI is the open-source chat front-end behind HuggingChat, designed to run with any Text Generation Inference endpoint. Hugging Face added MCP tool support in early 2026. Foldr is a practical add-on for teams running their own HuggingChat deployment who need a shareable-output story.
Installation
Add the Foldr MCP server to Hugging Face Chat UI with the snippet below. Replace fs_… with an API key from foldr.space/developers/signup. Each upload costs 5¢ - top up account credits or subscribe to Pro tier to bypass per-call charges.
# In .env.local
MCP_SERVERS='[
{
"name": "foldr",
"command": "npx",
"args": ["-y", "@foldr/mcp-server"],
"env": { "FOLDR_API_KEY": "fs_live_..." }
}
]'What You Can Do
- Upload any file from Hugging Face Chat UI to Foldr and get a permanent shareable URL back in the same turn (5¢ per upload, debited from credits)
- Mint short-lived capability tokens to share files with downstream agents without leaking your API key
- Organize uploads into per-API-key folders with hierarchical structure
- Shorten long URLs to foldr.space/s/... links - free with any API key
Hugging Face Chat UI + Foldr FAQ
How do I install the Foldr MCP server in Hugging Face Chat UI?
Open Hugging Face Chat UI's MCP configuration (the JSON settings file) and paste the config block shown above. Set FOLDR_API_KEY to a key you create at foldr.space/developers/signup. Restart Hugging Face Chat UI if it doesn't hot-reload.
How much does it cost to use Foldr from Hugging Face Chat UI?
Each upload costs 5¢. You can pay by topping up account credits via the `top_up_credits` MCP tool (min $5) - every upload then debits from balance. Or subscribe to Pro tier ($25/mo) and per-call charges are bypassed entirely. Tools that don't write data (list_files, mint_capability, get_usage, etc.) are free.
I set the key but Hugging Face Chat UI says the Foldr tool isn't available - what's wrong?
Three common causes: (1) Hugging Face Chat UI wasn't restarted after editing the config - most MCP hosts need a restart to pick up new servers. (2) The API key is wrong or missing - verify the env var name your client reads (e.g. FOLDR_API_KEY) matches the config snippet above. (3) Your client doesn't support the streamable-http transport - most modern clients do, but check Hugging Face Chat UI's docs for the version that added MCP support.
Can Hugging Face Chat UI upload files directly to Foldr, or just generate URLs?
Hugging Face Chat UI can do both. The MCP server exposes tools for `upload_file` (base64-encoded file content), `bulk_upload` (up to 20 files in one call), `mint_capability` (short-lived shareable links), and `create_short_url`. Any file Hugging Face Chat UI can read from disk can be uploaded.
Is the Foldr MCP integration with Hugging Face Chat UI production-ready?
Foldr's MCP server is stable and used in production - streamable-http transport at https://foldr.space/api/mcp with 23 tools. Hugging Face Chat UI's MCP support is currently experimental - expect rough edges and breaking changes. Every write endpoint accepts an Idempotency-Key so retries are safe.
Related MCP Integrations
Connect Hugging Face Chat UI to Foldr in under a minute
Grab an API key, paste the snippet above into Hugging Face Chat UI's MCP config, top up credits (or grab a Pro subscription), and your agent can upload files and mint share links immediately.